Responsivity performance of extended wavelength InGaAs shortwave infrared detector arrays

InxGa1-xAs ternary compound is suitable for detector applications in the shortwave infrared (1-3 μm) band. In this paper, we reported on mesa type and planar type extended wavelength InGaAs detector arrays. The photo response performances of these detector arrays were investigated. The blackbody responsivities (Rbb) of these detectors at different temperatures were measured, and the results showed that the Rbb of planar type arrays was higher than that of the conventionally passivated mesa type, but the mesa arrays fabricated by improved passivating technique has the highest responsivity. The reason of the Rbb difference between the arrays was analyzed, and it is found that the difference mostly comes from the minority carrier lifetime, which is related to the device structures and fabrication processes. With the optimized fabrication processes the mesa type arrays can obtain higher blackbody responsivity even more than the planar arrays.